package com.atguigu.gulimall.product.service.impl;

import org.apache.commons.lang3.StringUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.atguigu.common.utils.PageUtils;
import com.atguigu.common.utils.Query;

import com.atguigu.gulimall.product.dao.CategoryDao;
import com.atguigu.gulimall.product.entity.CategoryEntity;
import com.atguigu.gulimall.product.service.CategoryService;
import org.springframework.transaction.annotation.Transactional;


@Service("categoryService")
public class CategoryServiceImpl extends ServiceImpl<CategoryDao, CategoryEntity> implements CategoryService {

    @Autowired
    CategoryDao categoryDao;

    @Autowired
    CategoryBrandRelationServiceImpl categoryBrandRelationService;

    @Override
    public PageUtils queryPage(Map<String, Object> params) {
        IPage<CategoryEntity> page = this.page(
                new Query<CategoryEntity>().getPage(params),
                new QueryWrapper<CategoryEntity>()
        );

        return new PageUtils(page);
    }

    @Override
    public List<CategoryEntity> listWithTree() {
        //1.查出所有分类。
        List<CategoryEntity> entities = baseMapper.selectList(null);

        //2.组装成父子的属性结构

        //2.1 找到所有的一级分类
        List<CategoryEntity> level1Menus = entities.stream().filter(categoryEntity ->
                categoryEntity.getParentCid() == 0
        ).map((menu)->{
            menu.setChildren(getChildrens(menu,entities));
            return menu;
        }).sorted((menu1,menu2)->{
            return (menu1.getSort() == null ? 0: menu1.getSort()) - (menu2.getSort() == null?0:menu2.getSort());
        }).collect(Collectors.toList());


        return level1Menus;
    }

    //递归查找所有菜单的子菜单
    private List<CategoryEntity> getChildrens(CategoryEntity root, List<CategoryEntity> all){

        List<CategoryEntity> children = all.stream().filter(categoryEntity -> {
            return categoryEntity.getParentCid() == root.getCatId();
        }).map(categoryEntity -> {

            //1.找到子菜单
            categoryEntity.setChildren(getChildrens(categoryEntity,all));
            return categoryEntity;
        }).sorted((menu1,menu2)->{

            //2.菜单的排序
           return (menu1.getSort() == null ? 0: menu1.getSort()) - (menu2.getSort() == null?0:menu2.getSort());
        }).collect(Collectors.toList());
        return children;
    }

    @Override
    public void removeMenuByIds(List<Long> asList) {
        //TODO 1.检查当前的菜单是否被别的地方所引用

        baseMapper.deleteBatchIds(asList);
    }

    @Override
    public Long[] findCateLogPath(Long catelogId) {
         List<Long> paths = new ArrayList<>();
         paths = findParentPath(catelogId,paths);

         //收集的时候是顺序，前端是逆序显示的 所以用集合工具类给它逆序一下
        Collections.reverse(paths);
        return paths.toArray(new Long[paths.size()]);  //1级 2级 3级
    }

    /**
     * 递归收集所有父分类
     * @param catelogId
     * @param paths
     * @return
     */
    private List<Long> findParentPath(Long catelogId, List<Long> paths) {
        //1.收集当前节点
        paths.add(catelogId); //比如父子孙层级,返回的是孙 子 父
        CategoryEntity parent_id = this.getById(catelogId);
        if(parent_id.getParentCid() != 0)
        {
            //递归
            findParentPath(parent_id.getParentCid(),paths);
        }
        return  paths;
    }

    /**
     * 级联更新所有关联的数据
     * @param category
     */
    @Transactional
    @Override
    public void updateCascade(CategoryEntity category) {
        this.updateById(category);
        categoryBrandRelationService.updateCategory(category.getCatId(),category.getName());

    }
}